The present invention relates to an oil separating mechanism and an oil separating unit.
An oil separating mechanism is provided in a cylinder block having a concave portion opening outwardly at a sidewall thereof, and a cover member is attached to a peripheral edge of the concave portion to cover the same. The concave portion and the cover member form a closed space used for separating oil. As an example of a specific structure disposed in the closed space, Reference No. 1 has disclosed a structure in which a baffle plate is disposed in the closed space in a maze pattern. Reference No. 2 has disclosed a structure in which a partition wall having a communicating hole is provided in the closed space to divide the closed space into an outer chamber and an inner chamber. A baffle plate is provided in the inner chamber, and the outer chamber is provided with an opening-closing valve for allowing oil to flow in only from the inner chamber so that the outer chamber is used for housing the opening-closing valve.
Further, Reference No. 3 has disclosed a structure wherein a partition wall having a communicating hole is provided in the closed space to divide the closed space into an inner chamber and an outer chamber. The outer chamber is provided with an opening-closing valve for allowing oil to flow in only from the inner chamber, so that the outer chamber is used for housing the opening-closing valve. A pipe is provided at an opening portion of the communicating hole in the inner chamber.
According to the structures described above, blow-by-gas hits the baffle plate or the pipe to change a flow direction, so that oil mists contained in the blow-by-gas are separated.
Reference No. 1; Japanese Utility Model Publication (KOKOKU) No. 06-27778
Reference No. 2; Japanese Utility Model Publication (KOKAI) No. 57-182213
Reference No. 3; Japanese Patent Publication (KOKAI) No. 62-240413
In the oil separating mechanisms as described above, the process for separating the oil is a single step through either the baffle plate (Reference No. 1 and No. 2) or the pipe (Reference No. 3), so that it is difficult to achieve high separating performance.
In view of the above problems, the present invention has been made, and an object of the invention is to provide an oil separating mechanism with improved separating performance.
Another object of the invention is to provide an oil separating unit to be used for the oil separating mechanism.
Further objects and advantages of the invention will be apparent from the following description of the invention.